The present invention relates to a new and distinct cultivar of Heuchera and given the cultivar name of ‘Sweet Tart’. Heuchera is in the family Saxifragaceae. Heuchera ‘Sweet Tart’ originated from a controlled cross between Heuchera K273-1, a proprietary non-commercial hybrid, as the seed parent, and Heuchera K412-1, a proprietary non-commercial hybrid, as, as the pollen parent.
Compared to the seed parent, Heuchera K273-1, the new cultivar has lime rather than green leaves and a smaller habit.
Compared to the pollen parent, Heuchera K412-1, the new cultivar has a smaller habit and pink rather than red flowers.
Compared to Heuchera ‘Havana’, U.S. Plant Pat. No. 22,087, the new cultivar has more crowns, smaller leaves that are less lobed, bright pink rather than rose colored flowers, and is more free-flowering.
This new Heuchera is uniquely distinguished by:                1. small yellow spring leaves that mature to lime green,        2. bright pink flowers in wands,        3. very free-flowering and repeat blooming on short, dark flower stalks,        4. small, multi-crowned, low mounding habit, and        5. excellent vigor.        
This new cultivar has been reproduced only by asexual propagation (tip cuttings and tissue culture). Each of the progeny exhibits identical characteristics to the original plant. Asexual propagation by cuttings and tissue culture using standard micropropagation techniques with terminal and lateral shoots, as done in Canby, Oreg., shows that the foregoing characteristics and distinctions come true to form and are established and transmitted through succeeding propagations. The present invention has not been evaluated under all possible environmental conditions. The phenotype may change with variations in environment without a change in the genotype of the plant.